Fernand Seguin Research Center

Montréal, Canada

Fernand Seguin Research Center

Montréal, Canada
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Igue R.,Maisonneuve Rosemont Hospital Research Center | Potvin S.,Fernand Seguin Research Center | Potvin S.,University of Montréal | Bah R.,Maisonneuve Rosemont Hospital Research Center | And 11 more authors.
Progress in Neuro-Psychopharmacology and Biological Psychiatry | Year: 2011

Background: Some but not all antipsychotics have been shown to modulate plasma cytokine levels in schizophrenia patients. Thus far, the most consistent finding has been the increase in plasma levels of soluble interleukin (IL)-2 receptor (sIL-2R) associated with clozapine treatment. Quetiapine is a second-generation antipsychotic with a pharmacological profile similar to that of clozapine, but its immunomodulatory effects have not been investigated in schizophrenia yet. The purpose of this exploratory study was to examine the changes in plasma levels of sIL-2R in schizophrenia during quetiapine treatment and association with psychopathology. Methods: Participants were 29 schizophrenia-spectrum disorder patients (DSM-IV criteria), and 28 healthy controls. Patients had a comorbid substance use disorder (cannabis > alcohol > cocaine), since quetiapine is increasingly used in this population of dual diagnosis. No participant suffered from infection or overt inflammatory diseases. On baseline, patients taking mostly second-generation antipsychotics were switched to quetiapine for a 12-week open-label trial. Five patients were drop-outs. Mean dose of quetiapine for trial completers (n = 24) was 466.6. mg ± 227.3. Psychiatric variables were evaluated with the Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia. Plasma sIL-2R levels were assessed at baseline, weeks 6 and 12 in patients, and in healthy controls, using sandwich immunoassay. Plasma IL-6 and IL-1 receptor antagonist (IL-1RA) were measured for comparison purposes. Results: On baseline, plasma sIL-2R, IL-6 and IL-1RA levels were higher in dual-diagnosis patients, compared to controls. Plasma sIL-2R further increased after quetiapine treatment (p = 0.037), while plasma IL-6 and IL-1RA did not change. Clinical improvements were observed in positive, negative and depressive symptoms, and substance abuse severity (all p < 0.01). Interestingly, changes in sIL-2R levels during treatment were inversely correlated with changes in positive symptoms (r = -0.524; p = 0.009). That is, increases in sIL-2R levels were associated with reductions in positive symptoms. Conclusion: These data show that quetiapine elevates, like clozapine, sIL-2R levels in schizophrenia. Furthermore, the results suggest that sIL-2R alterations in schizophrenia rely on complex interplays between antipsychotics and the positive symptoms of the disorder. Future randomized controlled trials involving larger samples of schizophrenia patients are warranted to determine whether changes in plasma sIL-2R are quetiapine-related. © 2011 Elsevier Inc.

Giersch A.,French Institute of Health and Medical Research | van Assche M.,French Institute of Health and Medical Research | Huron C.,French Institute of Health and Medical Research | Luck D.,French Institute of Health and Medical Research | And 2 more authors.
Neuropsychologia | Year: 2011

We explore the mechanisms sub-tending the re-organization and memorization of visual information by studying how these mechanisms fail in patients with schizophrenia. Several studies have suggested that patients have difficulties in organizing information in perception and memory. We explore to what extent prompting patients to group items influences memory performance. We distinguish automatic grouping from top-down grouping processes, which are especially involved in re-organizing information. The main task was to memorize pairs of figures. Following manipulation of proximity, pairs of figures were part of the same perceptual group (within-group pair, formed on the basis of automatic grouping) or belonged to different groups (between-group pairs, re-grouped through top-down processes). Prior to the memory task, subjects ran a perception task prompting them to prioritize either within-group or between-group pairs. Unlike patients, controls globally benefited from grouping by proximity in the memory task. In addition, the results showed that prioritizing between-group pairs had a deleterious effect in patients, but with a large decrement in memory performance in the case of within-group rather than between-group figures. This occurred despite preserved focalization on within-group figures, as shown by eye-movement recordings. The suggestion is that when patients are prompted to re-group separate items, they can do so, but the benefit derived from automatic grouping is then not only lost but also reversed. This suggests re-organizing visual information not only involves re-grouping separate items but also integrating these new groups in a unified representation, which is impaired in patients with schizophrenia. © 2011 Elsevier Ltd.

Trudel G.,University of Quebec at Montréal | Trudel G.,Fernand Seguin Research Center | Villeneuve L.,University of Quebec at Montréal | Preville M.,Université de Sherbrooke | And 3 more authors.
Sexual and Relationship Therapy | Year: 2010

The following study gives results on the association between psychological distress and sexual and marital aspects from the Quebec Health Survey of Older Couples (Enquête sur lá sante des aînés au Québec/Volet Couple). In this study, 508 francophone couples (508 women, 508 men), aged 65 years old and over, answered several questionnaires about psychological distress (e.g. Psychological Distress Index) and marital (e.g. Dyadic adjustment scale) and sexual aspects of their life (e.g. Derogatis Sexual Functioning Inventory, International Index of Erectile Function, Female Sexual Function Index). Participants answered general questions at home in the presence of an interviewer and they answered to specific questionnaires about their sexuality and marital life on a computer to ensure confidentiality. Results indicate that dyadic adjustment, sexual satisfaction and gender predict psychological distress and explain 14.2% of the variance of psychological distress among older couples. The same predictor variables were found in men and women considered separately. Moreover, participants with low marital functioning show more than twice as much psychological distress and poorer sexual functioning. © 2010 British Association for Sexual and Relationship Therapy.

Foldes-Busque G.,University of Quebec at Montréal | Foldes-Busque G.,Laval University | Marchand A.,University of Quebec at Montréal | Marchand A.,Fernand Seguin Research Center | And 8 more authors.
American Journal of Emergency Medicine | Year: 2011

Purpose: This study aimed at (1) establishing the prevalence of paniclike anxiety in emergency department (ED) patients with unexplained chest pain (UCP); (2) describing and comparing the sociodemographic, medical, and psychiatric characteristics of UCP patients with and without paniclike anxiety; and (3) measuring the rate of identification of panic in this population. Basic Procedure: A structured interview, the Anxiety Disorders Interview Schedule for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, was administered to identify paniclike anxiety and evaluate patients' psychiatric status. Anxious and depressive symptoms were evaluated with self-report questionnaires. Medical information was extracted from patients' medical records. Main Findings: The prevalence of paniclike anxiety was 44% (95% CI, 40%-48%) in the sample (n = 771). Psychiatric disorders were more common in panic patients (63.4% vs 20.1%), as were suicidal thoughts (21.3% vs 11.3%). Emergency physician diagnosed only 7.4% of panic cases. Principal Conclusions: Paniclike anxiety is common in ED patients with UCP, and this condition is rarely diagnosed in this population. © 2011 Elsevier Inc.

Dumais A.,University of Montréal | Cote G.,University of Quebec at Trois - Rivieres | Cote G.,Philippe Pinel Institute of Montreal | Lesage A.,Fernand Seguin Research Center | Lesage A.,University of Montréal
Canadian Journal of Psychiatry | Year: 2010

Objective: To identify the clinical specificity of men with severe mental illness (aged 18 to 40 years) by legal status. Method: Our study compared 85 inmates with 66 involuntarily hospitalized patients (IHPs) and 50 voluntarily hospitalized patients (VHPs) with at least one Axis I diagnosis of psychosis or major affective disorder. Sociodemographics, medical information, and criminal history were drawn from interviews, medical records, and official criminal records. We used the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders to determine Axis I disorders and antisocial personality disorder (ASPD). Psychopathy was measured with the Psychopathy Checklist - Revised. Results: We found that inmates had a lower level of schooling (P = 0.001), were more likely to have been in an intimate relationship (P < 0.001), and were less likely to have a psychiatric hospitalization history (P < 0.001), compared with hospitalized patients. Inmates were also more likely to meet criteria for delusional disorders or psychosis not otherwise specified (P < 0.001) and major depression (P = 0.001). IHPs were more likely to meet schizophrenia spectrum disorder criteria (P < 0.001). Inmates had a higher level of comorbidity involving ASPD (P < 0.001), psychopathy (P < 0.001), and substance misuse (P < 0.001). IHPs showed an intermediate level between inmates and VHPs for these comorbid disorders. VHPs had the lowest level of comorbidity with Axis I psychiatric diagnosis. Conclusion: Our clinical specificity hypothesis was supported: different psychopathological characteristics and social functioning profiles were identified by legal status. Specific integrated treatments should be considered for inmates and IHPs.

Aardema F.,Fernand Seguin Research Center | Aardema F.,Concordia University at Montréal | Aardema F.,University of Montréal | O'Connor K.,Fernand Seguin Research Center | And 3 more authors.
Cyberpsychology, Behavior, and Social Networking | Year: 2010

This study utilizes an innovative experimental paradigm to investigate the effects of virtual reality (VR) on dissociative experience and the sense of presence. A nonclinical sample of 30 people were administered measures of dissociation, sense of presence, and immersion before and after an immersion in a virtual environment. Results indicate an increase in dissociative experience (depersonalization and derealization), including a lessened sense of presence in objective reality as the result of exposure to VR. Higher preexisting levels of dissociation and a tendency to become more easily absorbed or immersed were associated with higher increases in dissociative symptoms resulting from VR immersion. Results are discussed in terms of imaginative processes underlying the dissociative experience and potential implications to the treatment of anxiety disorders with VR. © 2010, Mary Ann Liebert, Inc.

Villeneuve K.,Fernand Seguin Research Center | Potvin S.,Fernand Seguin Research Center | Lesage A.,Fernand Seguin Research Center | Nicole L.,Psychotic Disorders Program
Schizophrenia Research | Year: 2010

Non-compliance with pharmacotherapy among persons suffering from schizophrenia disorders stands at an average rate of 42% and is the subject of numerous studies. However, no studies to date have addressed the specific question of non-compliance with psychosocial treatment. The present study therefore aimed to determine the rate of drop-out from psychosocial treatment and to assess the influence of factors on this rate. Method: A meta-analysis was conducted based on 74 studies of randomized clinical trials on psychosocial treatment among persons suffering from schizophrenia spectrum disorder. Results: A drop-out rate of 13% was obtained. Age, gender, duration of illness, duration of treatment, treatment setting and study quality affected drop-out rates. Conclusion: The 13% rate of drop-out from psychosocial treatment is markedly lower than the drop-out rate from pharmacotherapy studies. This finding supports the feasibility of evidence-based psychosocial treatment - which has, moreover, clearly been shown to be clinically effective - as part of a complete care program for schizophrenia. © 2010 Elsevier B.V.

Poirier-Bisson J.,University of Quebec at Montréal | Marchand A.,University of Quebec at Montréal | Marchand A.,Fernand Seguin Research Center | Pelland M.-E.,University of Quebec at Montréal | And 4 more authors.
Journal of Nervous and Mental Disease | Year: 2013

The aim of this study was to assess the incremental cost-effectiveness ratios (ICERs) of two brief cognitive-behavioral therapy (CBT)-based interventions and a pharmacological treatment, compared with usual care, initiated in the emergency department (ED) for individuals with panic disorder (PD) with a chief complaint of noncardiac chest pain. A total of 69 patients were followed up to 6 months. The primary outcome variables were direct and indirect costs of treatment and PD severity. Panic management (PM) had an ICER of $124.05, per the Anxiety Disorders Interview Schedule for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, severity score change (95% confidence interval [CI], $54.63-$314.57), compared with pharmacotherapy (paroxetine), with an ICER of $213.90 (95% CI, $133.51-$394.94), and brief CBT, with an ICER of $309.31 (95% CI, $151.27-$548.28). The pharmacological and CBT interventions were associated with a greater clinical improvement compared with usual care at posttest. PM presented a superior ICER, suggesting that it may be a promising treatment option to implement in EDs. Copyright © 2013 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.

Zerouali Y.,University of Québec | Herry C.L.,University of Québec | Jemel B.,University of Montréal | Jemel B.,Fernand Seguin Research Center | And 2 more authors.
IEEE Transactions on Biomedical Engineering | Year: 2013

Neural synchronization is a key mechanism to a wide variety of brain functions, such as cognition, perception, or memory. High temporal resolution achieved by EEG recordings allows the study of the dynamical properties of synchronous patterns of activity at a very fine temporal scale but with very low spatial resolution. Spatial resolution can be improved by retrieving the neural sources of EEG signal, thus solving the so-called inverse problem. Although many methods have been proposed to solve the inverse problem and localize brain activity, few of them target the synchronous brain regions. In this paper, we propose a novel algorithm aimed at localizing specifically synchronous brain regions and reconstructing the time course of their activity. Using multivariate wavelet ridge analysis, we extract signals capturing the synchronous events buried in the EEG and then solve the inverse problem on these signals. Using simulated data, we compare results of source reconstruction accuracy achieved by our method to a standard source reconstruction approach. We show that the proposed method performs better across a wide range of noise levels and source configurations. In addition, we applied our method on real dataset and identified successfully cortical areas involved in the functional network underlying visual face perception. We conclude that the proposed approach allows an accurate localization of synchronous brain regions and a robust estimation of their activity. © 2013 IEEE.

Zhornitsky S.,Fernand Seguin Research Center | Potvin S.,Fernand Seguin Research Center | Moteshafi H.,Fernand Seguin Research Center | Dubreucq S.,Fernand Seguin Research Center | And 2 more authors.
International Clinical Psychopharmacology | Year: 2011

The atypical antipsychotic, quetiapine, is frequently prescribed on-label and off-label for the treatment of a variety of psychiatric disorders. As quetiapine has variable affinity for dozens of receptors, its clinical effects should also show a large variation as a function of dose and diagnostic category. This study attempts to elucidate the dose-response and comparative efficacy and tolerability (metabolic data) of quetiapine across psychiatric disorders. A systematic search was carried out in the electronic databases, PubMed and EMBASE, using the keywords 'quetiapine' and 'placebo'. Both monotherapy and add-on studies were included. A total of 41 studies were identified. In unipolar and bipolar depression, studies consistently found quetiapine to be effective versus placebo, at doses of approximately 150-300 and 300-600mg per day, respectively. In bipolar mania, they consistently found quetiapine to be effective at doses of approximately 600mg per day. In acute exacerbation of schizophrenia, the majority of studies found quetiapine to be effective at doses of approximately 600mg per day; however, a few large studies found no difference versus placebo. In contrast, studies consistently found quetiapine to be more effective than placebo for stable schizophrenia. In obsessive-compulsive disorder, studies did not consistently find quetiapine to be effective at doses of approximately 300mg per day. However, studies may have underestimated the efficacy of quetiapine for obsessive-compulsive disorder due to concomitant administration of antidepressants and the utilization of treatment-refractory patients. In generalized anxiety disorder, studies consistently found quetiapine to be effective at doses of approximately 150mg per day. Finally, analysis of metabolic tolerability data suggests that even low doses of quetiapine may lead to increase in weight and triglycerides across psychiatric disorders. Interestingly, however, quetiapine-induced elevations in low-density lipoprotein and total cholesterol seem to be restricted to schizophrenia patients. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.

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